DESCRIPTION: In this R29 application, the investigator proposes to develop and refine computational tools for analyzing results obtained from radiation hybrid and linkage mapping, with a particular emphasis on integration of multiple maps. The investigator proposes to use a variety of maximum likelihood methods to determine the best way to integrate radiation hybrid maps in which data have been gathered from different radiation hybrid panels, as well as to integrate radiation hybrid map data with linkage map data. She will use data generated by several groups who have built radiation hybrid maps with three different hybrid panels designed to allow a range of resolutions (from several Mb to 50 kb) to be determined, data from several extensive linkage maps, and data from YAC maps where physical distance information can be estimated to allow comparisons of base pair, centiMorgan and centiRay distances to be made. Another significant part of this effort will be to improve the ability to build radiation hybrid maps with very large numbers of markers by modifying the MultiMap computer program, which was developed by the investigator for linkage mapping. She will also use these tools to participate in a recently begun mouse genome radiation hybrid mapping project. Finally, she proposes to develop web-based servers to allow outside users to calculate map positions, based on multiple public radiation hybrid and linkage maps, of a marker or set of markers.